氢光谱线

Can you fix a car engine?
::你能修车引擎吗?

It’s not as common any more, but there was a time when many people could work on their own cars if there was a problem. Today, engines are computerized and require specialized training and tools in order to be fixed. When people did their own repairs, it was sometimes a trial and error process. Maybe the spark plugs needed to be replaced. No, that didn’t fix the problem completely, but it was a start in the right direction. Science operates the same way. A theory that is developed may work for a while, but then there are data that the theory cannot explain. This means that it's time for a newer and more inclusive theory.
::这已经不常见了,但曾经有一段时间,如果出现问题,许多人可以在自己的汽车上工作。 如今,引擎是计算机化的,需要专门培训和工具才能修复。 当人们自己修理时,它有时是一个试验和错误过程。 也许火花塞需要被替换。 不,它没有完全解决问题,但是一个正确的开端。 科学也以同样的方式运作。 发展出来的理论可能有一段时间有效,但随后有数据理论无法解释。 这意味着现在该是更新和更具包容性的理论的时候了。

Spectral Lines of Hydrogen
::氢光谱线

Bohr’s model explains the spectral lines of the hydrogen atomic emission spectrum . While the of the remains in the ground state , its energy is unchanged. When the atom absorbs one or more quanta of energy, the electron moves from the ground state orbit to an excited state orbit that is further away. Energy levels are designated with the variable $\begin{align*}n\end{align*}$ . The ground state is $\begin{align*}n=1\end{align*}$ , the first excited state is $\begin{align*}n=2\end{align*}$ , and so on. The energy that is gained by the atom is equal to the difference in energy between the two energy levels. When the atom relaxes back to a lower energy state, it releases energy that is again equal to the difference in energy of the two orbits (see Figure ).
::Bohr的模型解释了氢原子排放频谱的光谱线。 虽然在地面的残余物处于状态,但其能量没有变化。 当原子吸收了一个或多个能量量时,电子从地面状态轨道移动到离地球更远的振动状态轨道。 能源水平与变量 n. 设定为 n=1 。 地面状态为 n=1, 第一个振动状态为 n=2 等。 原子获得的能量相当于两种能量水平之间的能量差异。 当原子向低能量状态后退时,它释放的能量与两个轨道的能量差异相同(见图 ) 。

The change in energy, $\begin{align*}\Delta E\end{align*}$ , then translates to light of a particular frequency being emitted according to the equation $\begin{align*}E=hv\end{align*}$ . Recall that the atomic emission spectrum of hydrogen had spectral lines consisting of four different frequencies. This is explained in the Bohr model by the realization that the electron orbits are not equally spaced. As the energy increases further and further from the nucleus , the spacing between the levels gets smaller and smaller.
::E=hv.回顾氢原子排放频谱的光谱由四个不同频率组成。Bohr模型对此的解释是认识到电子轨道的间距不相等。随着能量在核上进一步增加,水平之间的间距越来越小。

Based on the wavelengths of the spectral lines, Bohr was able to calculate the energies that the hydrogen electron would have in each of its allowed energy levels. He then mathematically showed which transitions corresponded to the spectral lines in the atomic emission spectrum ( Figure ).
::根据光谱线的波长,Bohr能够计算氢电子在每种允许的能量水平中的能量。然后他用数学来显示原子排放频谱中哪些转换与光谱线相对应(图 )。

He found that the four visible spectral lines corresponded to transitions from higher energy levels down to the second energy level $\begin{align*}(n=2)\end{align*}$ . This is called the Balmer series. Transitions ending in the ground state  $\begin{align*}(n =1)\end{align*}$ are called the Lyman series, but the energies released are so large that the spectral lines are all in the ultraviolet region of the spectrum. The transitions called the Paschen series and the Brackett series both result in spectral lines in the infrared region because the energies are too small.
::他发现,四条可见光谱线与从高能水平向第二级能源级(n=2)的转换相吻合,这称为Balmer系列。结束于地面状态的转换(n=1)称为Lyman系列,但释放的能量非常大,光谱线都位于频谱的紫外线区域。称为Paschen系列和Brackett系列的转换都导致红外区域的光谱线,因为能量太小。

Bohr’s model was a tremendous success in explaining the spectrum of the hydrogen atom. Unfortunately, when the mathematics of the model was applied to atoms with more than one electron, it was not able to correctly predict the frequencies of the spectral lines. While Bohr’s model represented a great advancement in the atomic model and the concept of electron transitions between energy levels is valid, improvements were needed in order to fully understand all atoms and their chemical behavior.
::布尔的模型在解释氢原子的频谱上取得了巨大成功。 不幸的是,当模型的数学应用到拥有不止一个电子的原子时,它无法正确预测光谱线的频率。 尽管博尔的模型代表了原子模型的巨大进步,而能源水平之间的电子转换概念是有效的,但需要改进才能充分理解所有原子及其化学行为。

Summary
::摘要

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• Emission lines for hydrogen correspond to energy changes related to electron transitions.
  ::氢排放线与与电子转换相关的能量变化相对应。
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• The Bohr model works only for the hydrogen atom.
  ::波尔模型只对氢原子起作用

Review
::回顾

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1. What happens when a hydrogen atom absorbs one or more quanta of energy?
   ::当氢原子吸收一种或多种能量量的量子时会怎样?
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2. How do we detect the change in energy?
   ::我们如何探测能源的变化?
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3. What electron transitions are presented by the lines of the Paschen series?
   ::Pashen系列系列的线路显示了什么电子转换?
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4. Does the Bohr model work for atoms other than hydrogen?
   ::波尔模型除了氢外 还能用原子吗?